Process for control of product density of spray-dried detergent compositions



" ing tetrasodium pyrophosphate,

. tion.

' portion of FOR CONTROL OF SPRAY-DRIED DETERGENT COMPOSITIONS Richard K. Fllteraft and William ll. Satkows'kl,

field, Paul J. Schauer, Danvers, and I L. LII, North Reading, Mass, asslgnors' to Monsanto lealCompany,St.Louis,Mo.,aeo|-pomtlonolDeh- No Drawing. Application December 20,1955 ,-SerlalNo.554,137

14 Clahm. cl. ass-11s This invention relates to the preparation of controlled density spray-dried detergent compositions. More specifi-' cally the process'of this invention relates to the prepara- 01' PRODUCT DW 1 .Wake- United States Patent-O "ice j predictable results were often obtained. Thus it was not unusual to have to store off-gradematerial that was outside the acceptable bulk density specification, which.

Patented Feb-'16, 1960 meant the added expense of storage jandhandling ofthe off-grade material and classifying in a manner which would permit latergradual blending off of the material where it could beused to modify subsequent production and the blended mixture had an apparent density within the specifications. According y, a simple, economical,

and efllcient means to control the density-of the product became a "critical problem.

, The principal object'of this invention is to provide an efiicient means of controlling the bulk density of lowsudsing, spray-dried detergent compositions within pretion of low-sudsmg, spray-dried detergent compositions Y containing a non-ionic. active constituent and a plurality of alkaline builder components sodium tripolyphosphate, sodium carbonate, sodium bicarbonate, the sodium sili-v cates, and the like, wherein a uniform product density is assured by the addition of a small amountof potassium v or sodium soaps of higher fatty acids and resin acids to the detergent slurry prior to spray The involved in the instant invention have been large volume commercial products for a number of years and their consumption is measured in millions of pounds per year.

This large production of material is marketed in relatively small cartons, as-for example, the nineteen-ounce and which are familiar to the ,home' three-pound package, consumer. It is essential that the weights be true with good measure to provide for minor variations with change bulk density would assure always being able to get the proper weight of material into the package, but the major 7 production ofo'ptimum bulk density would leave an undesirable amount of freeboard, or outage. in the package, and during periods of maximum bulk dencause the consumer to erroneously believe that she was getting short'measure and for the samereason would cause difficulties with packaging'regulations. The freeboard, or outage, is a measure of the fullness of -the package and is the measure of-empty space at-the top of the package, normally indicated as the linear measurement ,of the distance between the top-level surface of the product and the top of the package.

from the group comprisdrying said composiposition can beprepared by;altering a single variable in.

low-sudsing, spray-dried detergent compositions sity the amount of-freeboard would be so large as to I The freeboard has heretofore been controlled to re-' main within permissible limits by various combinations ofprocessing variables, as for example, changing the" spray tower operating conditions such as drying temperature employed, spraypressure, type of .spray nozzles, etc., and

various slurry treatments prior to spray drying such as altering the solidscontent, altering slurry milling time, altering temperature-timealtering aging time of slurry,

history of slurry, etc. Whereas a new combination of ,75 percent soap. The

the material will vary with the particular soap and con-.

scribed narrow limits. Another object gf this'invention "is to produce a uniform low-sudsing, spray dried detergent composition, which can be packaged directly 'at the co'u-' clusion of the normal manufacturing operations with out storing and blending off in subsequent operations. Still another object of this invention is to provide an eco'nomical process whereby a controlled-densitydetergent coma predictable manner rather than altering a combination unpredictable manner.

It has now been found that the'addition of upto about 1 percent of apotasslum or sodium soap to the non-ionic detergent slurry"composition-before spray drying pro vides a suitable means i the spray-dried product without altering the desirable 'of variables which have'heretofore often responded in an for controlling the bulk d'ensity of properties of the formulation. Preferably from about 0.3

to about. 0.5 percent of the soap is -employed'to obtain .thedesired'bulk density of about 0.28 to about 0.30 g./cc.

The aforesaid 'quantity of soap is based on the amount of'dry soap which is added to the detergent slurry composition. The soap may be added as an aqueous solution, gel or paste generally containing from about 30 to about actual physical characteristics of centration selected, but a liquid solution is generally preferred such that the soap can be readily metered into the detergent slurry. Preferably detergent compositions prepared for spray drying operations contain from about to about percent total solids, thereforeo'n a dry basis the preferredamountof soap will be from abou t 0.5 to about 0.9 percent of the'anhydrous mixture.

- The .detergent compositions can be directly made up with the full amount of the 'so'ap necessary to produce the desired-density. However it is often advantageous, espe:

cially when the detergent composition is formulated from a different lot ofv active material, to initially add only a portion of the soap to the detergent slurry-and thcn'add the balance of the soap necessary'lo produce the desired bulk density as determined by the properties of the product obtained from the first portion of the drying operation for the particular batch of slurry.

The soaps include the potassium and sodium salts of the higher fatty acids, i.e., those containing from 12 to'l8 carbon atoms, and the resin'acids, e.g., lauric .acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, .abietic acid, 'pyroabietic acid, dehydroabietic acid, dihydroabietic acid, l-sapietic acid, d-pimaric acd, agathic acid, etc., or.'thc soaps can be prepared directly from the wholeoils predominantly containing the aforesaid acids, e.g., tall oil,- coconutoil, palm kernel oil, palm oil, olive I oil, cottonseed oil, linseed oil, peanut oil, soybean oil, com

processing-conditions tendedto give a partial control, this solution to the problem was not a true control, since un oil, castor oil, hydrogenated marine oil, and the like. Potassium tallate is the preferred soap since it is readily available, it is derived from one of the more economical sources of organic acids, and its composition is particularly compatible and effective for the non-ionic detergent,

slurry compositions.

The potassium tallate is prepared by the neutralization of the tall oil in a solution of potassium hydroxide. Acoordingly, the term potassium tallate as employed herein is defined to mean the tall oil acids potassium soap composition. Preferably the potassium tallate is ob tained as liquid containing 30 to .35 percent potassium tallate, which material can be readily incorporated'into the detergent slurry.

Tall oil is a well known article of commerce, obtained as a by-product of the sulfate pulp industry, essentially comprising a mixture of unsaturated and saturated fatty acids and rosin acids. Tall oil is thus by nature subject to considerable variation in composition being in part dependent on the species of wood processed, the season of the year the tree was felled, the age of the tree, the

storage life of the wood, the procedure for processing the chips and converting the black liquor into tall oil, etc. Thus the average analysis of tall oil from fifteen mills ranged from 36 to 54 percent fatty acids, 38 to 58 percent rosin acids, and 6 to 18 percent unsaponifiable material. The fatty acids of tall oil are primarily unsaturated fatty acids, principally oleic and linoleic in substantially equal amounts, with a small content of saturated fatty acids, predominantly palmitic. Abietic acid is the predominant rosin acid of tall oil. Whereas solvent refined tall oil is preferred for the preparation of potassium tallate crude tall oil may be employed, but may tend to impart an off-white color and an odor to the spray-dried detergent composition. Other grades of tall oil, such as distilled tall oil, can be employed as desired.

The improved process of this invention may be generally employed in spray drying detergent compositions which are based on a non-ionic active constituent and a lurality of alkaline builder components from the group comprising tetrasodium pyrophosphate, sodium tri-poly phosphate, sodium carbonate, sodium bicarbonate, the sodium silicates, and the like. The non-ionic active constituent is generally a condensation product of the lower alkylene oxides containing up to 4 carbon atoms, for example, ethylene oxide, propylene oxide, butylene oxide, and mixtures thereof, with a compound, or compounds, having one or more active hydrogen atoms, as for example, aliphatic mercaptans, alkyl phenols, fatty acids, alcohols, and the like, which compounds preferably have a molecular weight of less than about 400. The mole ratio of alkylene oxide to aetive-hydrogen-containing compound is from about 3 to about 20 and preferably from about 9 to about 15. Illustrative detergent compositions are disclosed, for example, in US. Patents No.

2,522,446, 2,522,447, 2,550,691, 2,572,805, and 2,594,- 453.

The detergent compositions disclosed in US. Patent No. 2,550,691 are particularly suitable to the process of this invention. The detergent slurry is generally formulated to contain from about 45 to about 60 percent by weight total solids, and preferably from about 55 to about 60 percent by weight total solids, which on an anhydrous basis can be selected from the following illustrative comy} positions, all parts being by weight:

To the above product may be added from 0.1 to

parts of carboxymethyl cellulose.

Parts Condensation product of one part of tall oil with 1.6 parts of ethylene oxide 15.00 Tetrasodium pyrophosphate 40.00 Soda ash 20.25 Sodium silicate (GC silicate) Na,O:SiO,=l:2 24.00 Carboxy methyl cellulose 0.75

B Condensation product of one part of tall 'oil with 1.8 parts of ethylene oxide 20 Sodium tripolyphosphate Sodium carbonate 15 Sodium silicate Na,O:Si0,=l:3.2 l0 Starch 14 Carboxy methyl cellulose 1 C v Condensation product of one part of tall oil wi 2.0 parts of ethylene oxide 15.00 Tetrasodium pyrophosphate 40.00 Soda ash 20.15 Sodium silicate solution (water glass, 38% solids,

62% water) Na-,O:Si0,=1:3.2 24.00 Carboxy methyl cellulose......-.. 0.75 Perfum 0.10

Condensation product of one part of tall oil with 1.6 parts of ethylene oxide.. 15 Sodium tripolyphosphate 20 Tetrasodium pyrophosphate 20 Soda ash 20 4 Other more specific illustrative compositions, are as follows, all parts being by weight:

Sodium silicate solution (38% solids) Na,0:

Si0 =l: 7 v Sodium carboxy methyl cellulose 1 Following the preparation of the desired aqueous tietergent slurry the soap is added thereto and mixed therein to provide a homogeneous slurry. The amount of soap necessary to obtain the desired bulk density of the spray-i dried product will vary depending on slurry formulation modifications, the particular non-ionic active employed and its past history, such as age, storage conditions, treatment, etc., but up to about 1 percent by weight, based on the weight of the detergent slurry composition, has been found to be suitable. For greater ease of control it is preferred that the non-ionic active employed be freshly prepared and treated in a uniform manner. However non-uniform lots of active can also be readily employed in the process of this invention by initially adding only a portion of the amount of soap required when a freshly prepared active is employed, and thereafter adding additional increments thereof, as necessary, during the spray drying operation.

The following examples are illustrative of the process of this invention.

A series of batches of detergent slurries containing about 55 percent solids and essentially consisting of formulation D, shown above, were prepared, varying amounts of potassium tallate, as a heavy paste containing 75 percent solids, were added thereto, and reduced to a homogeneous mixture. The slurries were continually agitated to maintain a uniform composition throughout the drying operation and held at a temperature of about 45-50 C. The slurries were pumped to the spray nozzles of the drying tower and atomized at a nozzle pressure of about 500 p.s.i. into the hot gas (320-325' C.) of the spray chamber and dried in the usual manner employed in spray drying operations well known to the art. Each of the batches of slurry were treated under as nearly identical conditions as possible, such that the only variable was the quantity of potassium tallate preeassasso ent in the formulation. The spray-dried detergent compositions were found to vary in bulk density as shown in the following table. a I I In addition to the essential components shown in the.

formulations listed above, minor. quantities of other materials can'be added as desired, for example a fluorescent dye, perfumes, etc.

the dried product to preclude loss in. the drying operation. The spray-dried product can also further treated; as disclosed in the copending application of Paul 1.

Schauer, Serial No. 513,580, filed June 6, 1955, or by other 1 procedures known to. the art. v

We claim:

1. In the process of manufacturing a 'spray-drieddetergent composition, the steps whichcomprise the formulation of an aqueous detergent slurry, containing from about 45 to about 60 percent total solids, of a non-ionic active constituent and a plurality of alkaline builder components, wherein the non-ionic active detergent constituent is a condensate of an active-hydrogen-containing compound having a molecular weight of less than about 400 and a lower alkylene oxide containing up to 4 carbon atoms, the alkylene oxide to activc-hydrogen-contain ing compound mole ratio being from .about 3 to about 20 and the detergent composition on a solids basis consists of the following components, wherein all parts are parts by weight: .to 30 parts of non-ionic active constituent, to 60 parts of alkaline phosphate builder salts, 10 to 40 parts of non-phosphate builder salts, up to parts sodium silicate, up to 25 parts starch, and 0.1

-up to 1 percent, by weight of the detergent slurry composition of a soap selected from potassium and sodium salts of the higher fatty acids containing from 12 to 18 carbon atoms, the resin acids, and mixtures thereof to the said. slurry; and spray drying said slurry; whereby the bulk density of thespray-dried detergent composition varies as an inverse function of the quantity of soap employed.

2. In the process of manufacturing a spray-drieddetergent composition, the steps which comprise the formulation of an aqueous detergent slurry, containing about 45 to about 60 percent total solids, of a non-ionic active constituent and a plurality of alkaline builder components, wherein the non-ionic active detergent constituent The perfume is of course added to Parts Condensation product of one part of tall oil with 1.8 parts, of ethylene oxide Sodium tripolyphosphate 40' Sodium carbonat 15 Sodium silicate Na O:Si0,=1:3.2

' Starch" t 14 Carboxyl methyl cellulose l percent total solids, which on an anhydrous basis comprises the following components, all parts being by weight:

Parts Condensation product of .tall oil with ethylene oxide intbe ratio of 0.5:2.3 per part. of tall oil 10-25 Tetrasodiurn pyrophosphate, sodium tripolyphosphate, and mixtures thereof 20,-60

Sodium silicate, NagOzSiO, ratio of 1:2 to 1:3.2 6-25 Alkaline material selected from the class consisting of sodium carbonate, sodium bicarbonate and mixtures thereof 10-25 Carboxy methyl cellulose 0.1-5

4. The process of claim 2, wherein the aqueous detergent slurry consists of from about 45 to about 60 percent total solids, which on a solids basis comprises the follow- .ing components, all parts being by weight:

5. The process of claim 2, wherein theaqueous detergent slurry consists of from about 45 to about 60 percent Parts Condensation product of one part of tall oil with 2.0 parts of ethylene oxide 15.00 Tetrasodium pyrophosphate 40.00 Soda ash 20.15 Sodium silicate solution (water glass, 38% solids,

62% water) Na O:SiO -1:3.2 24.00 Carboxyl methyl cellulose 0.75 Perfume 0.10

. gent slurry consists of from about to about 60 percent 5 pans of carbbxy methyl cellulose; the addition of 7 total solids, which on a solids basis comprises the followthe group consisting of I Parts Condensation product of one part of tall oil with 1.6

parts of ethylene oxide '15 Sodium tripolyphosphate 20 Tetra'sodium pyrophosphate 20 Sodaash 20 Sodium silicate solution (38% solids) Na OSSiO =1=3.2 j 24 Sodium carboxy methyl cellulose l is a condensate of an active-hydrogen-containing comfloat-id having a molecular weight of less than about 400 and a lower alkylene oxide containing up to 4 carbon atoms, the alkylene oxide to active-hydrogen-containing compound mole ratio being from about 3 to about 20 andthe detergent composition on a solids basis consists of the following components, wherein all parts are parts by weight: 10 to 30 parts of non-ionic active constituent, 20

to 60 parts of alkaline phosphate builder salts, 10 to 40 parts of non-phosphate builder salts, up to 25 parts so-.

6. The process of claim 2, wherein the aqueous detering components, all parts being by weight:

7. The process of claim 3, wherein the addition of potassium tallate consists of from about.0.3 to about 0.5 percent by weight of the slurry composition;

8. Theprocess of claim 3, wherein the aqueous detergent slurry contains the following components in parts by weights 9. The process of claim 4, wherein the detergent slurry contains from about to about percent by weight total solids, and the addition of potassium tallate consists of from about 0.3 to about 0.5 percent by weight of theslurry composition.

10. The process of claim 5, wherein the detergent slurry contains from about 55 to about 60 percent by weight total solids, and the addition of potassium tallate 7 consists of from about 0.3 to about 0.5 percent by weight of the slurry composition.

11. The process of claim 6, wherein the detergent slurry contains from about 55 to about 60 percent by weight total solids, and the addition of potassium tallate consists of from about 0.3 to about 0.5 percent by weight of the slurry composition.

12. The process of claim 7, wherein the detergent slurry contains from about 55 to about 60 percent by weight total solids.

13. The process of claim 8, wherein the detergent slurry contains from about 55 to about 60 percent by weight total solids, and the addition of potassium tallate consists of from about 0.3 to about 0.5 percent by weight of the slurry composition.

. 14. The process of controlling the bulk density of a spray-dried, non-ionic active based detergent composition, comprising the formulation of an aqueous detergent slurry, containing from about 45 to about 60 percent total solids, of a non-ionic active constituent and a plurality of alkaline builder components, wherein the nonionic active detergent constituent comprises from about 10 to about 25 percent by weight on an anhydrous basis of the detergent composition and is a condensate of (A) an active-hydrogen-containing compound having a molecular weight of less than about 400 selected from the group 8 consisting of the higher fatty acids, resin acids, aliphatic mercaptans, alcohols, alkyl phenols, and mixtures thereof, and (B) a lower alkylene oxide containing up to 4 carbon atoms, the alkylene oxide to active-hydrogen-containing compound mole ratio being from about 3 to about 20; the addition thereto of up to 1 percent, by weight of the detergent slurry composition, of a soap selected from the group consisting of potassium and sodium salts of the higher fatty acids containing from 12 to 18 carbon atoms, the resin acids, and mixtures thereof to the said slurry; mixing said soap to provide a substantially homogeneous composition; and spray drying said slurry; wherein the bulk density of the spray-dried detergent composition is characterized by a value which varies as an inverse function of the quantity of soap employed.

References Cited in the file of this patent UNITED STATES PATENTS 2,277,728 Thomas et a1 Mar. 31, 1942 2,294,075 Colgate et al Aug. 25, 1942 2,308,992 Mertens .4. Ian. 19, 1943 2,560,839 Ayo et a1. July 17, 1951 2,673,186 Wheelock et a1 Mar. 23, 1954 2,697,695 McDonald Dec. 21, 1954 2,770,600 Ricciardi Nov. 13, 1956 line 60 after "Condensation"? insert product UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 2325 390 February 16, 1960 Richard K. Flitcraft et a1.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 2 line 641:, for "acd" read acid column 6,,

Signed and sealed this 9th day of August 1960.

(SEAL) Attest:

KARL AXLINE ROBERT C. WATSON Attesting Oflicer Commissioner of Patents 

1. IN THE PROCESS OF MANUFACTURING A SPRAY-DRIED DETERGENT COMPOSITION, THE STEPS WHICH COMPRISE THE FORMULATION OF AN AQUEOUS DETERGENT SLURRY, CONTAINING FROM ABOUT 45 TO ABOUT 60 PERCENT TOTALS SOLIDS, OF A NON-IONIC ACTIVE CONSTITUENT AND A PLURALITY OF ALKALINE BUILDER COMPONENTS, WHEREIN THE NON-IONIC ACTIVE DETERGENT CONSTITUENT IS A CONDENSATE OF AN ACTIVE-HYDROGEN-CONTAINING COMPOUND HAVING A MOLECULAR WEIGHT OF LESS THAN ABOUT 400 AND LOWER ALKYLENE OXIDE CONTAINING UP TO 4 CARBON ATOMS, THE ALKYLENE XOIDE TO ACTIVE-HYDROGEN-CONTAINING COMPOUND MOLE RATIO BEING FROM ABOUT 3 TO ABOUT 20 AND THE DETERGENT COMPOSITION ON A SOLIDS BASIS CONSISTS OF THE FOLLOWING COMPONENTS, WHEREIN ALL PARTS ARE PARTS BY WEIGHT: 10 TO 30 PARTS OF NON-IONIC ACTIVE CONSTITUENT, 20 TO 60 PARTS OF ALKALINE PHOSPHATE BUILDER SALTS, 10 TO 40 PARTS OF NON-PHOSPHATE BUILDER SALTS, UP TO 25 PARTS SODIUM SILICATE, UP TO 25 PARTS STARCH, AND 0.1 TO 5 PARTS OF CARBOXY METHYL CELLULOSE, THE ADDITION OF UP TO 1 PERCENT, BY WEIGHT OF THE DETERGENT SLURRY COMPOSITION OF A SOAP SELECTED FROM THE GROUP CONSISTING OF POTASSIUM AND SODIUM SALTS OF THE HIGHER FATTY ACIDS CONTAINING FROM 12 TO 18 CARBON ATOMS, THE RESIN ACIDS, AND MIXTURES THEREOF TO THE SAID SLURRY, AND SPRAY DRYING SAID SLURRY, WHEREBY THE BULK DENSITY OF THE SPRAY-DRIED DETERGENT COMPOSITION VARIES AS AN INVERSE FUNCTION OF THE QUANTITY OF SOAP EMPLOYED 